Stator of motor for washing machine

ABSTRACT

Disclosed is a stator of a motor for a washing machine including: a stator core manufactured by a plurality of steel sheets laminated on top of each other, the stator core having a core base and a plurality of teeth radially formed on the core base; an upper insulator which covers the upper parts of the core base and the teeth to insulate them, the upper insulator having least three upper fastening parts which are formed therein and each of which has an upper fastening hole; and a lower insulator which covers the lower parts of the core base and the teeth to insulate them, the upper insulator having least three upper fastening parts which are formed therein and each of which has a lower fastening hole.

CROSS REFERENCE TO PRIOR APPLICATIONS

This application is a National Stage Application of PCT InternationalPatent Application No. PCT/KR2014/005285 filed on Jun. 17, 2014, under35 U.S.C. § 371, which claims priority to Korean Patent Application No.10-2014-0038576 filed on Apr. 1, 2014, which are all hereby incorporatedby reference in their entirety.

TECHNICAL FIELD

The present invention relates to a stator of a motor for a washingmachine, and more particularly, to a stator of a motor for a washingmachine which can prevent noise and vibration while operating and reducemanufacturing costs.

BACKGROUND ART

In general, a motor for a washing machine includes a rotor and a stator.The stator includes a stator core in which a number of steel sheets arelaminated on top of each other and an insulator surrounding the statorcore. Such a structure of the stator is disclosed in U.S. Pat. Nos.7,336,014 and 7,362,028 and U.S. Patent Publication No. 2011/0036127.

In U.S. Pat. No. 7,336,014, the stator has a structure that an upperinsulator and a lower insulator which come in contact with each otherand surround nearly all of the inner circumferential surface of a statorcore. Such a structure may generate noise by a fine vibration near theboundary of the two insulators when a motor is operated, and requirerelatively lots of resin molding because the insulators cover most ofthe inner circumference of the stator core.

In U.S. Pat. No. 7,362,028, because a fastening part is formed by theupper insulator and the lower insulator which come into contact witheach other, the problems of vibration, noise and increase ofmanufacturing costs are not solved. Moreover, one or more fasteningprojections protrude inwardly from a hole of the connected part, but inthis instance, the fastening projection is cut out by a sleeve when thesleeve is forcedly pressed, and hence, it generates foreign matters.

In U.S. Patent Publication No. 2011/0036127, a fastening part is formedonly at the upper insulator and is not formed at the lower insulator,but such a structure is weak in fastening strength because only oneinsulator is fastened to the stator core. Furthermore, such a structurealso does not solve the problems of the fine vibration and noise.

Therefore, in order to solve the above problems, the inventors of thepresent invention propose a new structure of a stator of a motor for awashing machine.

DISCLOSURE OF INVENTION Technical Problem

Accordingly, the present invention has been made in an effort to solvethe above-mentioned problems occurring in the prior arts, and it is anobject of the present invention to provide a stator of a motor for awashing machine which can prevent noise and vibration while operating

Another object of the present invention is to provide a stator of amotor for a washing machine which can reduce manufacturing costs.

The above and other objects, features and advantages of the presentinvention will be apparent from the following detailed description ofthe preferred embodiment of the invention in conjunction with theaccompanying drawings.

Solution to Problem

To achieve the above objects, the present invention provides a stator ofa motor for a washing machine including: a stator core manufactured by aplurality of steel sheets laminated on top of each other, the statorcore having a core base and a plurality of teeth radially formed on thecore base; an upper insulator which covers the upper parts of the corebase and the teeth to insulate them, the upper insulator having leastthree upper fastening parts which are formed therein and each of whichhas an upper fastening hole; and a lower insulator which covers thelower parts of the core base and the teeth to insulate them, the upperinsulator having least three upper fastening parts which are formedtherein and each of which has a lower fastening hole, wherein apredetermined space is formed between the inner circumferential surfaceof the upper insulator and the inner circumferential surface of thelower insulator, and the inner circumferential surface of the core baseis exposed through the space.

In the embodiment of the present invention, the stator further includesa damper which is joined between the upper fastening part and the lowerfastening part and which has a central hole, wherein the upper fasteninghole, the lower fastening hole and the central hole are formed atpositions corresponding to one another.

In the embodiment of the present invention, an upper damper seating partwhich has an upper damper insertion hole is formed inside the upperfastening hole, a lower damper seating part which has a lower damperinsertion hole is formed inside the lower fastening hole, an upperprotrusion part formed at the upper part of the damper is inserted intothe upper damper insertion hole, and a lower protrusion part formed atthe lower part of the damper is inserted into the lower damper insertionhole.

In the embodiment of the present invention, the stator further includesa bush which is fastened to the upper fastening hole, the central holeand the lower fastening hole.

In the embodiment of the present invention, an upper strengthreinforcing part 102 is formed around the upper fastening part 100, anda lower strength reinforcing part 202 is formed around the lowerfastening part 200.

Advantageous Effects of Invention

The stator of the motor for the washing machine according to theembodiment of the present invention can prevent noise and vibrationwhile operating and reduce manufacturing costs.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view showing a stator of a motor for a washingmachine according to a preferred embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a part of the stator ofthe motor for the washing machine according to the preferred embodimentof the present invention.

FIG. 3 is a bottom side perspective view of an upper insulator used inthe stator of the motor for the washing machine.

FIG. 4 is a top side perspective view of a lower insulator used in thestator of the motor for the washing machine.

Reference will be now made in detail to the preferred embodiment of thepresent invention with reference to the attached drawings.

MODE FOR THE INVENTION

FIG. 1 is a perspective view showing a stator 1 of a motor for a washingmachine according to a preferred embodiment of the present invention.

As shown in FIG. 1, the stator 1 of the motor for the washing machineaccording to the preferred embodiment of the present invention includesan upper insulator 10, a lower insulator 20 and a stator core 30.

The stator core 30 is manufactured by a plurality of steel sheetslaminated on top of each other, and the upper part and the lower part ofthe stator core 30 is insulated by the upper insulator 10 and the lowerinsulator 20. When the upper insulator 10 and the lower insulator 20 arejoined to the upper part and the lower part of the stator core 30, theinner circumferential surface of the upper insulator 10 and the innercircumferential surface of the lower insulator 20 do not come intocontact with each other but are spaced apart from each other at apredetermined interval. The stator core 30 is exposed through theinterval to be visible to the naked eyes.

At least three upper fastening parts 100 and at least three lowerfastening parts 200 are respectively formed on the inner circumferencesof the upper insulator 10 and the lower insulator 20. The upperfastening part 100 and the lower fastening part 200 are opposed to eachother and respectively have holes, such that one bush 50 penetrates theholes of the two fastening parts 100 and 200. Dampers 40 may beselectively joined to the upper fastening part 100 and the lowerfastening part 200. A bolt (not shown) penetrates through the inside ofthe bush 50, so that the stator 1 is fastened to a motor set (notshown).

FIG. 2 is an exploded perspective view showing a part of the stator ofthe motor for the washing machine according to the preferred embodimentof the present invention.

Referring to FIG. 2, the upper insulator 10 of the stator 1 of the motoraccording to the preferred embodiment of the present invention isfastened to the upper part of the stator core 30, and the lowerinsulator 20 is fastened to the lower part of the stator core 30.

The stator core 30 includes a rounded core base 31, and a plurality ofteeth 32 radially formed around the rounded core base 31. A core innercircumferential surface 33 is located on the inner face of the core base31.

Because the upper insulator 10 covers the upper part of the stator core30, the upper insulator 10 includes an upper base cover part 11 forcovering the upper part of the core base 31, an upper teeth cover part12 for covering the upper part of the teeth 32, and an upper innercircumference cover part 13 for covering the inner circumference 33. Theupper fastening parts 100 which are located at predetermined positionsof the upper inner circumference cover part 13 protrude inwardly. A tapterminal 14 to be connected with an external power supply is formed at apredetermined position of the upper base cover part 11.

An upper fastening hole 101 for inserting the bush 50 is formed in theupper fastening part 100. A damper 40 may be joined to the inner face ofthe upper fastening part 100. An upper strength reinforcing part 102 maybe formed at the lower part of the upper fastening part 100 in order toreinforce strength of a protruding part. Moreover, an aligning hole 110for taking a correct position when the stator 1 is fastened to the motorset may be formed at one side of the upper fastening hole 101 of theupper fastening part 100.

FIG. 3 is a bottom side perspective view of an upper insulator used inthe stator of the motor for the washing machine.

As shown in FIG. 3, the upper insulator 10 according to the preferredembodiment of the present invention includes the upper base cover part11 which covers the core base 31 of the stator core 30 and the upperteeth cover part 12 which covers the teeth 32. The inner circumferentialsurface of the upper insulator 10 forms the inner circumference coverpart 13, and at least three upper fastening part 100 which are formed atpredetermined positions are formed on the upper inner circumferencecover part 13. A damper seating part 103 to which the damper 40 isconnected may be formed around the upper fastening hole 101. The upperdamper seating part 103 has an upper damper insertion hole 104, and thedamper 40 is connected when an upper protrusion part 42 of the damper 40is inserted into the upper damper insertion hole 104. A central hole 41of the damper 40 has the same size as the upper fastening hole 101 andis formed at the same position, such that the bush 50 can penetrate theupper fastening hole 101 and the central hole 41.

In case that the aligning hole 110 is formed in the upper fastening part100, a plurality of empty spaces 13 a are formed around the aligninghole 110 to thereby reduce an amount of resin molding. Moreover, theempty spaces 13 a which are formed inside the upper inner circumferencecover part 13 can reduce manufacturing costs by reducing the amount ofresin molding.

The damper 40 is made of a material which can absorb shock andvibration, such as rubber, in order to provide a buffer action andvibration-proof function, but it is not restricted to rubber, andvarious materials, such as silicon, aluminum die casting, plastic ormetal, may be applied as occasion demands. The damper 40 has the centralhole 41 through which the bush 50 penetrates, and the upper protrusionpart 42 and the lower protrusion part 43 are respectively formed at theupper part and the lower part of the central hole 41. The upperprotrusion part 42 is located in the upper damper insertion hole 104formed inside the upper fastening part 100 and around the upperfastening hole 101 when the damper 40 is fastened to the upper and lowerfastening parts 100 and 200.

FIG. 4 is a top side perspective view of a lower insulator used in thestator of the motor for the washing machine.

As shown in FIG. 4, the lower insulator 20 includes a lower base coverpart 21 which is a part to cover the core base 31 of the stator core 30and a lower teeth cover part 22 which is a part to cover the lower partof the teeth 32. The inner circumference of the lower insulator 20 formsthe lower inner circumference cover part 23, at least three lowerfastening parts 200 which are formed at predetermined positions areformed on the lower inner circumference cover part 23.

Each of the lower fastening parts 200 has a lower fastening hole 201. Alower damper seating hole 203 to which a damper 40 is joined may beformed around the lower fastening hole 201. The lower damper seatingpart 203 has a lower damper insertion hole 204, such that a lowerprotrusion part 43 of the damper 40 is inserted into the lower damperinsertion hole 204 to thereby fasten the damper 40. The lower fasteninghole 201 has the same size as the central hole 41 of the damper 40 andthe upper fastening hole 101 and is formed in the same position, suchthat the bush 50 can penetrate the upper fastening hole 101, the centralhole 41 and the lower fastening hole 201.

It is preferable that the upper insulator 10 and the lower insulator 20be symmetric with each other, but it is not necessarily so. It is alsopreferable that the damper 40 has a top and bottom symmetrical structurein such a manner that the upper protrusion part 42 and the lowerprotrusion part 43 are formed symmetrically, but it is not necessarilyso.

As described above, at least three upper fastening parts 100 are formedon the upper inner circumference cover part 13 of the upper insulator10, and preferably, they are formed symmetrically to each other. If theupper fastening part 100 is opposed to the lower fastening part 200corresponding to the upper fastening part 100 and one bush 50 can beinserted into the upper fastening part 100 and the lower fastening part200, there is no need for the upper fastening parts 100 to have the sameshape, and the same applies to the lower fastening parts 200. In FIGS. 1to 3, it is illustrated that the aligning hole 110 is formed in theupper fastening part 100, but it is not restricted to theabove-mentioned form. For instance, the aligning hole 110 may be formedin the upper inner circumference cover part 13 without regard to theupper fastening part 100.

In a state where the upper insulator 10 and lower insulator 20 arefastened to each other, the upper inner circumference cover part 13 andthe lower inner circumference cover part 14 do not come into contactwith each other. Therefore, also the upper fastening part 100 and thelower fastening part 200 do not come into contact with each other in thestate where the upper insulator 10 and lower insulator 20 are fastenedto each other. The part where the upper fastening part 100 and the lowerfastening part 200 do not come into contact with each other is an openpart, and the core inner circumferential surface 33 of the stator core30 is exposed to the outside through the open part. Through such astructure, the stator of the motor according to the preferred embodimentof the prevent invention can reduce an amount of required resin moldingand prevent fine vibration and noise generated at the boundary part.

The stator core 30 is formed by the steel sheets laminated on top ofeach other, and in this instance, the steel sheets may be wound in aspiral form or may be stacked on top of each other on just one steelplate according to a laminating method.

As described above, while the present invention has been particularlyshown and described with reference to the example embodiment thereof, itwill be understood by those of ordinary skill in the art that the aboveembodiment of the present invention are all exemplified for yourunderstanding and are not to limit the technical scope of the presentinvention. It should be also understood that the protective scope of thepresent invention is interpreted by the following claims and alltechnical ideas within the equivalent scope belong to the technicalscope of the present invention.

The invention claimed is:
 1. A stator of a motor for a washing machinecomprising: a stator core manufactured by a plurality of steel sheetslaminated on top of each other, the stator core having a core base and aplurality of teeth radially formed on the core base; an upper insulatorwhich covers the upper parts of the core base and the teeth to insulatethem, the upper insulator having least three upper fastening parts whichare formed therein and each of which has an upper fastening hole; alower insulator which covers the lower parts of the core base and theteeth to insulate them, the lower insulator having least three lowerfastening parts which are formed therein and each of which has a lowerfastening hole; and a damper which is joined between the upper fasteningpart and the lower fastening part and which has a central hole, whereinthe upper fastening hole, the lower fastening hole and the central holeare formed at positions corresponding to one another, wherein apredetermined space is formed between the inner circumferential surfaceof the upper insulator and the inner circumferential surface of thelower insulator, and the inner circumferential surface of the core baseis exposed through the space.
 2. The stator according to claim 1,wherein an upper damper seating part which has an upper damper insertionhole is formed inside the upper fastening hole, a lower damper seatingpart which has a lower damper insertion hole is formed inside the lowerfastening hole, an upper protrusion part formed at the upper part of thedamper is inserted into the upper damper insertion hole, and a lowerprotrusion part formed at the lower part of the damper is inserted intothe lower damper insertion hole.
 3. The stator according to claim 1,further comprising: a bush which is fastened to the upper fasteninghole, the central hole and the lower fastening hole.
 4. The statoraccording to claim 1, wherein an upper strength reinforcing part isformed around the upper fastening part, and a lower strength reinforcingpart is formed around the lower fastening part.